Used to define a linear function A -⚬ B in a point-full style, i.e. as a lambda expression.
Used to define a linear function A -⚬ B in a point-full style, i.e. as a lambda expression.
Recall that when defining A -⚬ B, we never get a hold of a: A as a Scala value. However, by using this method we get a hold of a: $[A], a placeholder variable, and construct the result expression $[B]. This method then inspects how the input variable a: $[A] is used in the result $[B] and infers a (point-free) construction of A -⚬ B.